_:n7161863490224898b511a6f4d6e033b6xb1
<http://schema.org/isAccessibleForFree>
"true"^^<http://www.w3.org/2001/XMLSchema#boolean>
<https://bmcpediatr.biomedcentral.com/articles/10.1186/s12887-021-02645-9/tables/4>